Using EagleTree's MicroPower eLogger as a bike computer...

[GGoodrum]

I have been beta testing a new V3 version of EagleTree's MicroPower eLogger,and decided that since this new version has an 80V limit, vs 50V for the previous versions, I would give it a try on one of my bikes. There is also now a razor thin remote display that goes with it, called a a PowerPanel.

The eLogger records voltage, current, motor rpm and a couple different temp sensors. There are three types of rpm sensors: hall/magnetic, optical and a brushless motor sensor that connects to one if the three motor wires and counts pulses. There is a PC application that not onlys lets you replay the dat, realtime, but also has a flexible charting module.

What makes this particularly useful with our ebike applications is by using the PowerPanel, which allows the live display of any number of recorded and/or calculated parameters. You have complete control of what gets displayed, and in what order. There is room to display 4 items at a time, but you can have it display multiple pages, either automatically, at a selectable rate, or it can be switched manually, via a switch.

For rpm, I'm initally using the magnetic hall unit, piggy-backed on a speedometer sensor. I'm also going to try the brushless sensor, but I need to figure out how many poles a 5303 "Racer" has, in order to calibrate the sensor. I'm also planning to try hooking a line directly into in of the motor's hall sensors. I'm told that should work fine. In any case, there is a way to enter a formula in the PC app so that bike speed, in MPH, or km/hr, can be displayed in the PC replay, on te PowerPanel or plotted with the graphing module.

One the coolest things you can do with these is to overlay the playback of recorded data onto a video made at the same time, so that they are syncronized.

Anyway, I did such a video yesterday. The file is pretty big (146mb...), but it started as HD. I scaled it down slightly, to about 3/4 HD. You can watch it here:

http://www.tppacks.com/video/Mariner-20s4p-5303-11-02-07.wmv

The video is of my 20" Dahon Folding bike, with a 5303 and a 20s4p a123 setup. It now has an upgraded controller, with the 4110s and has the current limit raised to what turns out to be about 88A. As yolu will see in the video, this has turned this machine into a real beast. The squealing you hear in the video is the tire breaking loose from too much power. As you can see, it easily hits multiple 5500W/87A peaks. The acceleration is ungodly. Here's a graph showing voltage, current, watts an Ah used:

Here's some shots of the setup, incluing the camera mount and the eLogger and PowerPanel mounting:

Also mounted is a WattsUp, which I used to verify/calibrate the eLogger readouts.

I didn't have the rpm sensor connected, for this recordedc ride, but I will for the next one, which I hope to do tomorrow

-- Gary

 

[fechter]

Excellent! The price is reasonable too.

5500w !? Holy burnout!
Bet that surprises the heck out of the lycra boys.

I don't remember the pole count on the motor. I think you want to know the number of magnets. I have one I could look at. Otherwise you could just guess a number, then see how far off the speed is. Once you know that, you can refine the guess by doing some math.

 

[fechter]

I just watched the video.

That's insane! You must go through tires fast.

Time for the Fechter adjustable current limit mod....

The instrument overlay on the video is fantastic.
There's another item for the wish list.

 

[EMF]

I don't remember the pole count on the motor.

The 400 series has 8 and the 5300 series has 12

Yes a lot of watts! Also, the 80+ amps caught my eye.

 

[GGoodrum]

I just watched the video.

That's insane! You must go through tires fast.

Time for the Fechter adjustable current limit mod....

The instrument overlay on the video is fantastic.
There's another item for the wish list.

Yeah, I need to get some beefier tires, for sure.

I agree, this needs the current limit mod. but I need to get a little more of this out of my system first. It's like the old adage, "Once they've seen Paris, it is hard to get them back down on the farm..." :wink:

I'm going to try the brushless sensor today. I'll try using 12-poles first (thanks, EMF...), and see how that does. Right now, I'm using the "airplane" user interface option in the PC application. It has a calibration option for using a prop gearbox, or for the gearing on a helicopter's rotor, that I have used with a calculated value to turn the wheel/motor rpm into MPH (you could do the same thing for km/hr...). The PowerPanel setup will show this calculated MPH readout, and the PP setup dialog lets you change the label displayed, but I can't do this for the regulat Airplane UI playback. There is also a Car UI option, that will actually be better suited for for this, as it has a regular speed gauge that can be displayed, but there is a bug in the beta software right now that keeps the Car UI from being able to be used with the eLogger. Also, the speed calibration used in the Car UI is weird, and requires another funny conversion to have it convert wheel rpm into MPH (or km/hr...). I am promised that if this works out, and we can come up with a usable setup, they will do a dedicated eBike UI, that lets you simply enter wheel size, and maybe gearing, for those that aren't using hubmotors, and that will have better choices for what gets shown in the replay.

Most of what is there is already usable. The PP, for instance, not only shows voltage, current, watts, and Ah used, but when you are stopped, the displays switch to show peak watts, peak amps and the lowest value that the pack voltage dipped down to since power was first applied.

On my Townie, I already have the magnetic sensor installed, as I was originally going ot test the eLooger using it, but when I put the modified controller on the Mariner (and saw "Paris"... ), I decided the eLogger needed to go on it first. I've got a second modified controller on its way back from Bob that will go on the Townie this week, and then I'll do some more testing with the eLogger. the Townie has a 5304, but has 26" tires that are much beefier, so it will be interesting to see how it does with all this power. I don't really know the top speed of eithre bike on 20s a123s, but it is somewhere north of 40 mph. While I was hanging on for dear life, I tried to glance at the regular speedometer on the handlebars, but it was hard to read. I think I was hitting about 36-37 mph, but I'm too scared to take it much beyond that point. It sure gets there in a hurry, though.

One thing I really like about this setup is that you keep the eLogger in back, close to the controller and the packs, and be able to mount the PowerPanel wherever you want. It just has a small 4-wire cable. On my Townie, I put the PP on the handlebars.

Granted, this doesn't have an adjustable current limiter function (but Richard has taken care of that...), but it does do data logging, and it is still about half the price of a Cycle Analyst. As for the rest of the functions, it is only software, and they have told me they will support an eBike application, so we'll see.

-- Gary

 

[Drunkskunk]

Looks like a nice unit. How far past 80V can it handle? my packs have a resting voltage of 85V.

 

[GGoodrum]

Looks like a nice unit. How far past 80V can it handle? my packs have a resting voltage of 85V.

I'm not sure yet. Their test setup only let them go to 80V. I will try higher numbers, but they are also going to look at this as well. They also told me that if the market is big enough, they can do a special HV model for ebikes that can use higher rated parts.

-- Gary

 

[RLT]

Wow, that's amazing! I'm going to have to get one of those eventually.

And that GPS expander coupled to Google Earth just blows my mind.

 

[knoxie]

Hi

Great video!! super quality as well, some amazing figures on there 4KW 80A! fantastic stuff, how warm was he motor getting? they should be ok for that kind of power as Lowell has been running similar levels on his rig.

I would be interested to know the kind of speed you are getting, you could most definitely do with a current limiter or a current adjustable throttle, I use a limiter on mine and it works like a charm, I noticed a lot of high pitch whine from the motor? was the apparent or just the mic on the camera, you could fit a line reactor in series with the phase wires of it got too noisy, although it would burn up a few watts.

Fantastic video though, would love to see the speed displayed something I was going to do and never did! I fear that kind of power would be way too much for the Puma but it doesn't need it, at 72V 35A I cant stop the wheel spinning! and you will go through tyres, even at 37V the little BMX eats them and sometimes you develop so much power the rim spins inside the tyre! I have had that happen, it destroys the beading and you get an instant pinch flat.

Would love to see more videos though, those packs are amazing, did you get Bob Mcree to modify the controller for you? how are the drop outs looking with all that power?

The nice thing about a current limiter will be being able to turn the power down if you get stopped! ha ha, I have a feeling you may get one or 2 looks!!

Thanks for sharing

Knoxie

 

[Ypedal]

Video quote " Whoa " lol... Damn.. now look what you've done... i need me one of those ! 8)


That much power on the front of a folder.. ?


Do the amps ramp up smoothly if you apply throttle slowly or does it jump suddenly ?

Great job G ! keep up the good work ! :wink:

 

[GGoodrum]

Hi

Great video!! super quality as well, some amazing figures on there 4KW 80A! fantastic stuff, how warm was he motor getting? they should be ok for that kind of power as Lowell has been running similar levels on his rig.

I would be interested to know the kind of speed you are getting, you could most definitely do with a current limiter or a current adjustable throttle, I use a limiter on mine and it works like a charm, I noticed a lot of high pitch whine from the motor? was the apparent or just the mic on the camera, you could fit a line reactor in series with the phase wires of it got too noisy, although it would burn up a few watts.

Fantastic video though, would love to see the speed displayed something I was going to do and never did! I fear that kind of power would be way too much for the Puma but it doesn't need it, at 72V 35A I cant stop the wheel spinning! and you will go through tyres, even at 37V the little BMX eats them and sometimes you develop so much power the rim spins inside the tyre! I have had that happen, it destroys the beading and you get an instant pinch flat.

Would love to see more videos though, those packs are amazing, did you get Bob Mcree to modify the controller for you? how are the drop outs looking with all that power?

The nice thing about a current limiter will be being able to turn the power down if you get stopped! ha ha, I have a feeling you may get one or 2 looks!!

Thanks for sharing

Knoxie

I hit max peaks around 5550W and 87A. When Bob upgraded this controller with the 4110 mod, he also filled in 2 of the 4 shunt bars. This has apparently raised the current limit from about 38A to 87A. This is real silly power, way more than is probably safe for this thing, but man what a rush!

I'm too scared to really open this up full throttle, and see what the real top-end would be, but I did steal a glance at the handlebar-mounted speedometer yesterday in one stretch where I was holding on for dear life, and it was 38 MPH. I tried hooking up the brushless motor sensor yesterday, but the readings were all over the place, so I need to consult with ET and see what is going on here. I can't see an easy way to get access to the motor's hall sensors without cutting wires, or I'd try hooking one of these directly into the eLogger's magnetic rpm sensor input, which is also hall-based. I also have an optical sensor, so I think I will try that today, and see if I can't get the speed readout going.

The video starts out as HD, which is why the quality looks so good. In order to keep the files size "managable" and so that you don't need a machine with enough graphics horsepower to make a 14-year old wet his pants to play the video, I downrez it slightly to about 3/4 HD (960 x 540). At full HD resolution on a big HD plasma/LCD it looks even better.

The 5303 doesn't get hot at all. It was barely warm to the touch after the ride in the video. The dropouts look exactly like they've always looked, but who knows. I don't plan on pushing this too much more, in any case. I should be getting my second upgraded controller back from Bob today or tomorrow, and it will go on my Townie, which is a lot beefier than this folding bike, and much better suited for this sort of power. I'm going to try adding Richard's current limiting pot upgrade on this one, so that I can will lessen the chance that I'll end up folding this thing unexpectedly.

-- Gary

 

[vanilla ice]

A special hv ebike version, that would be nice of them. Not that I'd need the hv version. But that thing is very compact. I want one.

 

[GGoodrum]

Video quote " Whoa " lol... Damn.. now look what you've done... i need me one of those ! 8)


That much power on the front of a folder.. ?


Do the amps ramp up smoothly if you apply throttle slowly or does it jump suddenly ?

Great job G ! keep up the good work ! :wink:

You can set the rate at which the data gets stored from once a second, up to 10 times a second. I use the default, which is 4 times a second. It seems that if I really honk on the throttle, it takes about 3-4 readings to go from zero to 87A.

-- Gary

 

[GGoodrum]

A special hv ebike version, that would be nice of them. Not that I'd need the hv version. But that thing is very compact. I want one.

I think they are very close to finishing the testing up, and making these available. I just need to get the rpm stuff sorted out, and get them to do a calibration dialog that allows you to simply enter wheel size, and that's it. I think we are talking days, not weeks. Also, when they are ready, I'll have them on my site as well.

 

[Drunkskunk]

Well, as soon as there is one avalable that can handle atleast 85 volts, they have one sold


As I see it, this isn't a replacement for a Cycle Analyst. The CA does things like limit current and speed as an interface for the Clyte controller, and is weather resistant. This is more of a data tool, to be used when setting up a bike, or checking how batteries are doing over time. in otherwords, I need both!

 

[Ypedal]

Well, as soon as there is one avalable that can handle atleast 85 volts, they have one sold

!

Make that 2 ! *( actually 3.. as i'll take 2 myself ! ) 8)

 

[GGoodrum]

With the previous 50V versions, where I needed to use them with higher voltage setups, I used to simply connect them to the first pack in series. We had a number of 12s LiPo setups in helicopters, that were usually made up using two 6s LiPo packs, so I would just connect this to the first 6s pack in series. Then, in the PC app, you can "calibrate" the readout so that it converts it into the full 12s voltage. You could do the same thing here, but I'd prefer to not have the hassle.

In any case, the initial v3 units will be good for 80V, and then I'm going ot see about getting them to do a 100V version.

-- Gary

 

[knoxie]

Hi

Yes I agree both the CA and this unit go hand in hand, I don't use mine all the time only for videos and new motors, once I have got the data I just leave the Watts up plugged in, I don't run more than 48V on a daily basis so the watts up is all I need.

The current adjust is easy to do and does work well, You could prob get up to 38 mph with a lot less so having the adjust will be much kinder to the controller and motor, I am sure the batteries will be ok

I would keep an eye on the drop outs, I am assuming that you are also running a torque arm? if not id get one on there real quick, the torque at the axle will open those dropouts in no time otherwise.

The damage the Puma did to 4 pieces of mild 2mm mild steel was scary, so much so that I fitted 2 x 3mm stainless arms and its even bending them a little!

This is a scary level of power from such an unassuming little bike! most e-bikes that can perform like that look like mopeds in all honesty but this one doesn't!

Please be careful that is a bag load of power! and the way it comes in is pushing things on a little bike like that, hats off to the pack though that's quite something, I haven't got anything that can get near to that level of power, I can do 80A but only at 37V, the Puma would strip its cogs in no time I am sure. The new steel Puma though could handle it mechanically however It could not handle 4KW in the windings for very long! 1 to 1.5KW is ok on the Puma that's quick enough for me!!

Be great to see some external shots of the bike running so I can gauge the speed? and see that wheel light up!!

Thanks again for a great super high quality video.

Knoxie

 

[GGoodrum]

Yes, I most definitely have a big steel torque arm installed that is firmly attached to the fork.

I'll probably set the current limit to about 50-55A. That should be plenty to get me up and down most any hill around here quite comfortably. Besides, this really my "travel" bike, that I take down to a place we have down in San Diego. It is very flat there, so even this is overkill.

As I said, my 26" Townie is much better suited for a high power setup. It as a beefy frame and big fat tires. I can actually do 35-40 mph without ending up with laundry problems.

More videos soon...

-- Gary

 

[knoxie]

Hi

Yes glad you got an arm fitted! looking forward to the new videos already! I must get out and do something soon not messed about for a while, steel gears in the Puma and a bit more power will be the next thing.

Cheers

Knoxie

 

[solarbbq2003]

you guys put any thoughts into logging slope with them??
seems only variable that missing?
http://www.zc-sensor.com/en/Main/products.asp?CateID=6&CateName=Inclinometer

 

[solarbbq2003]

new x5 has 24magnets, not sure if that equates to 12 poles?? Might have to check if the magnets have multiple poles built into them, I haven't ever thought to check that

 

[The7]

new x5 has 24magnets, not sure if that equates to 12 poles?? Might have to check if the magnets have multiple poles built into them, I haven't ever thought to check that

Should 12 pole-pairs ( or 24 poles).

 

[mace1934]

Gary,

Many thanks for this post. I've been running a front 408 with 72 V controller and 20S3P A123s on my old Rockhopper. It's a great setup, but the motor tends to get hot on the final climb to my home, so I have to go slow and pedal some. I've been thinking of going with a 5305 (I'm not into speed, but would like to pull a trailer). So glad to know how well yours works!

I also use an older version of the Eagletree micrologger, and, as you did with your older one, attach it to only one of the 10S packs. Glad to know the new ones will go to 80V; Eagletree's original announcement said the V3 is good only for 60 V, so I decided to pass. Now I will get one. I fried a V2 at a little over 40V.

Great work and great movie!

(A bit on my bike: http://gristmill.grist.org/story/2007/9/5/93344/11653 )

Larry

 

[GGoodrum]

Hi Larry, and welcome.

I love the solar array! Can you tell more about this? Where did you get it? How many volts does it put out? What sort of electronics do you need for charging? This is fascinating.

Boy, you are really getting some very good "mileage". Your average Wh usage is less than half what mine is typically, and that was before Bob Mcree raised the current limit on my unit and put in the higher power FETs. With a 37A limit, I was seeing "burn" rates of around 40 Wh/mile. It is pretty hilly around here, and I'm anything but petite ( ), but still, 19 Wh/mile is very good. Now, with the ability to hit 85A/5500W peaks, I don't even want to know what kind of mileage I'm down to. The other day I did a little test run, which was only 1.67 miles. It consumed 1487 mAh, or about 890 mAh/mile. I don't remember how many Wh it consumed, but I think this works out to something north of 55 Wh/mile. It's a real watt guzzler now. In any case, the motor seems quite happy. I haven't seen it get hot yet.

I'm still having a few issues with the beta V3 ET unit, but they are getting sorted out. The brushless RPM sensor inputs are a bit "spikey", so they want to change the value of a capacitor, and the PowerPanel tends to come up with all the LCD pixels on when power is first applied with the packs right off the charger (around 72-73V...). This also required a capacitor change. Coincidently, the value the PP needed was what came off the brushless sensor, and vice-versa, so all that was needed to fix both issues was to swap capacitors. What I'm waiting on now is for them to fix the "Car" user inteface option so that it works with the Micro eLogger. that will allow the display of the analog speed gauge that shows MPH or km/hr.

-- Gary